System of regulation for dynamo-electric machines.



V. G. APPLE. SYSTEM ,OF REGULATION FOR DYNAMO ELECTRIC MACHINES. APPLICATION FILED APR. 12, 1912.

1,091,420. I Patented Mar. 24,1914.

. a citizen of the United States,

'- vINcn NT G. APrLE, on DAYTON,

or DAYTON, 01110, A CORPORATION 01110, ASSIGNOR TO THE I APPLE ELECTRIC COMPANY, or 01110.-

SYSTEM'OF REGULATION FOR DYNAMIC-ELECTRIC MACHINES.

To all whom it may concern:

Be it known that I, VINCENT G. APPLE, residing at Dayton, in the county of Montgomery and State of Ohio, have invented certain new and useful Improvements in Systems of Regulation for of which the following is a specification.

My invention relates to improvements in systems of regulation for dynamo-electric machines.

One of the objects of my -1I1V6nt10n is to provlde means whereby to automatically.

regulate dynamo electric machines, to maintain constant the current or the potential funder varying conditions of load, or speed.

I accomplish these results by varying substantially the ampere-turns of the field magnet windings by automatically introducing therein and withdrawing therefrom, in rapid succession, at variable intervals having variable time periods, a resistance, having a very hightemperature ooefiicient. In other words, the object is attained by,vary1ng the frequency of the intervals and by varying the time of duration of each interval] in which theresistance remains in circuit with, or is withdrawn from circuit of, the field windings whereby to change, or vary, the magnetic flux of the field magnets.

Other and further objects of my invention will readily become apparent to persons skilled in the art from a consideration'of the following description taken in conjunction with the drawing wherein Figure l is a diagrammatic view showing the manner of regulating for maintaining a constant current. Fig 2 is a similar view showing the manner-of regulating for maintaining constant difference of potential. In all of the views the same reference characters indicate similar parts.

In carrying my invention into efi'ect I, preferably, employ a vibrating relay 5, provided with an adjustable weight 5.

I will first describe the operation of the system when employed for regulating for constant current. The armature 6 is contained within a field, having a series winding 7 that is connected in series with the armature and with .the working malns 8 8 and translating devices 9 9. Another winding, winding the series 7, and when energized it opposes Specification of Letters Patent. Application filed April 12, 19-12.

Dynamo-Electric- Machines,

-ferential winding 10, by wire are left open tically 10, is in shunt relation with the' spondingly less winding so as to reduce the mag-- Patented Mar. 24, 1914. Serial No. 690,246.

netic flux, through the armature, and hence the electro-motive-force at the brush terminals 11, 12.- The electro-magnet 5 has a responsive armature 13 pivoted, as at 14 and when not energized it is held against the stop 15 by the adjustable retractile spring 16. The armature carries a contact 17 at its free end which is adapted to make electrical connection with the stationary contact 18 when the magnet 5 is sufliciently energized to attract the armature 13 against the effect of the retractile spring 16. The contacts 17 and 18 are bridged by a resistance 19,'by wires 20 and 21. The contact 18 is connected to the high resistance difarmature 13 is connected to the terminal of .the series winding 7, by. Wire 23, as at '24.

contacts 17-18, the difieren- Thus, through 10 shunts the series field 7.

tial winding The winding 10 and the resistance 19 are in series relation,

when contacts 17 and 18 are open and when so related they are in parallel circuit with the series winding 7. When the contacts are closed, then only the winding 10 is in parallel relation with the series winding 7.

The resistance '19 is preferably of iron .wire which has a relatively high temperature c'oeflicient. That is to say its resistance increases rapidly as the heat increases, being of much less resistance when cold. Best results are obtained when the resistance 19 has approached a temperature where it becomes visible, when the contacts 17 and 18 for a sufficient period of time. If the iron wire 19 were permanently to remain in normal atmosphere for any considerable period of time it would rapidly oxidize andsoon disintegrate to such an extent 'as'to be-practically worthless. Therefore I have found itadvantageous to inclose it within a glassenvelop from which pracall of the air has been removed and the receptacle then sealed.

22, and the The operation of the's'eries regulator is as follows: When current in the main 8 reaches a predetermined. value, the armature 13 is attracted against the effect of the retractile spring 16, until contacts 17 and l8. are

closed, then the resistance 19 is thereby short circuited and. more current will now flow through the differential coil 19,. and correthrough the series Winding 7, thereby reducingth'e magnetic flux of the tion of the field magnet, which will have the efiect of reducing the electro-motive-force of the armature. Now when the current flowing through the main 8 and the magnet 5 has been thus reduced, the spring 16 will overcome the effect of said magnet and retract the armature 13, once more opening contacts 17 and 18, thereby admitting the resistance 19 in circuit with the winding 10, and permitting coil 7 to again predominate. When the device 19 is thus cut out of circuit, it rapidly cools and its resistance correspondingly decreases, so that when it is again out into circuit, by opening of the contacts 17 and 18, there is practically no spark at the terminals 17 and 18 at the time of their separation as the resistance through 19 when cold is not much greater than the resistance through the armature 13 and contacts 17 and 18. The increase of resistance, or a substantial part thereof, is due to the energizadevice 19 when heated by the current that passes through it. The use of the resistance 19, arranged in circuit with the other devices as described, therefore gradually decreases the differential efl'ect of winding 10 upon the series field 7 by interposing in the circuit of said winding 10 a gradually increasing resistance, until finally the armature 6, with its field opposed by winding 10 in less degree than initially, causes current enough in the wire 8 to energize electromagnet 5 again; and during the energization of the electromagnet 5 the resistance 19 is cut out of circuit with the winding 10 to render the latter effective in opposing the series field 7, the resistance 19 in the meantime cooling to be again. ready for inclusion in circuit with the coil 10 when said coil 10 has by its effect upon-the field caused reduction of current in wire 8 and retraction of contact 17 from stationary contact 18.

A conductor, in substitution for the wire 19, and which has a low temperature coefiicient, such as copper, or the like, and which has not been heated to the desired temperature by the current passing through it, will not satisfactorily operate in the manner heretofore described, and a carbon lamp, in which the resistance rapidly decreases, as the filament rises in temperature will not serve the purpose for satisfactory or practical regulation. Therefore, it is just as well to understand that my invention is limited to the use of a conductor 19, wherein the resistance rapidly rises as the temperature is increased and wherein the temperature is materially increased by the passage of a current in the process of regulation, and wherein the intermissions, in which the current is admitted, are of less duration, in the matter of time, than the time required for the resisting element mum resistance by the effect of the current.

to reach its maxi-,

Fig. 2 shows the manner of regulation for a constant potential dynamo, wherein the magnet coils 5 are placed in parallel circuit with the armature 6 and the translating devices 9-9 across the mains 88, and the resistance 19 is in series with the usual shunt field-winding 7 When the potential across the mains rises to an abnormal degree, the magnet 5 attracts its armature 13opening the contacts 17 and 18, admitting the resistance 19, in series with the field windings 7, thereby causing decreased magnetic flux through the armature 6 and corresponding reduction of electro-motive-force. The gradual increase of resistance, due to in creased temperature of the rheostatic device 19, after it has been admitted into circuit, produces ideal conditions of regulation. It will be admitted into circuit in periods varying in point of time with the necessity of its presence, but never of longer duration than the time required for the rheostatic device to reach maximum resistance, and its increased resistance will be in correspondence with the time length of such periods.

The speed of vibration of the electro responsive device 5 may be varied by movement of the inertia weight 5 farther from or closer to the point of fulcrum of the armature 13.

My invention I have found to be especially valuable in connection with small dynamos such as are used for furnishing current for sparking internal combustion engines used on automobiles, and for lighting a few incandescent lamps for illumination in connection with such vehicles, and

for such purposes it has proven to be thoroughly reliable and eflicient, although it may be adapted for use with much larger dynamos and I, therefore, do not desire to be limited in its use to small machines.

While I have herein described two exemplifications of the use of my invention it is evident that it is subject to further modification without departure from the scope of the appended claims.

What I claim is:

1. A system of regulation comprising a dynamo'electric machine, a circuit supplied thereby, a field-winding for the dynamo, a. rheostatic conductor, connections for associating said conductor with the field winding for said dynamo electric machine whereby the resistance of said conductor reduces the magnetic flux of said field winding, said rheostatic conductor being of a character such that its resistance is materially increased I by the efi'ect of current therethrough,

means responslve to electrical variations in thecircuit'for said dynamo electric machine and a short circuiting switch controlled by said means, to cut sald conductor in or out of circuit.

2. A systemaof regulation comprising, in 1 combination with a dynamo electric-machine having a field winding, a rheostatic conductor the resistance of which materially increases by the effect of the current therethrough, circuit connections for inclusion of said conductor to oppose the effect of said field winding in gradually increasing degree, and means responsive to electrical vari ations in the circuit for said dynamo electricmachine, for cutting out said conductor.

3. A system of regulation comprising, in-

combination with a dynamo electric-machine and a field winding therefor, a rheostatic conductor, connections for associating said conductor with the circuit for said dynamo electric-machine and with the field winding for said dynamo electric-machine whereby the resistance of said conductor reduces the magnetic flux of said field winding, said rheostatic conductor being of a character such that its resistance materially increases by the effect of the current therethrough, means responsive to electrical variations in the circuit for said dynamo electric-machine, and a shortcircuiting switch controlled by said means I to cut said rheostatic conductor in orout of circuit to affect 'said field winding and through it the electrical conditions of said circuit for the dynamo electric-machine.

In testimony whereof I hereunto set my hand in the presence of two witnesses.

VINCENT G. APPLE. In the presence of- N. E. SNYDER, E. V. MARTIN 

